Police officers line the streets near the funeral of Officer Wenjian Liu. / ASSOCIATED PRESS

Responding to growing public anger over police tactics, the police unions in St. Paul and Minneapolis issued a letter appealing to residents to "understand the danger of contributing to these often false or inaccurate publicly-broadcast narratives."

In the letter, John Delmonico, head of the Police Officers Federation of Minneapolis, and Saint Paul Police Federation president David A. Titus, doubled down on their criticism of protesters who have taken to the streets of cities across the country, angered by recent grand jury decisions not to indict white police officers in the deaths of unarmed black men. The two leaders pointed to a link between the protesters' anti-police rhetoric and a wave of attacks targeting officers, including the shoot deaths of two New York City policemen last month.

The letter said:

It continued:

Authorities have said that Ismaaiyl Brinsley, the Georgia man who allegedly killed the two NYPD officers, frequently posted anti-police and anti-government messages on social media.

Delmonico, long a staunch defender of police officers, has come under fire for suggesting that the protesters "are unable or unwilling to accept just how violent our society is" and that the "simple solution" to use of force by officers is to "obey the law and those entrusted to enforce it."

Delmonico's words echoed those of his counterparts in New York City, who have accused the city's mayor, Bill de Blasio, of fanning anti-police sentiment by publicly questioning the grand jury decision not to indict a white NYPD officer in the death of Eric Garner. Hundreds of NYPD officers turned their backs on de Blasio as he spoke at the funerals of their slain colleagues in Brooklyn.

In a letter to President Barack Obama and Congressional leaders this week, police union leaders argued that violence motivated by anti-police sentiment should be prosecuted as a hate crime.